1. Field of the Invention
The present invention relates to a vehicle engine controller that controls an engine based on an accelerator position sensed with an accelerator sensor.
2. Description of Related Art
There is a vehicle mounted with a recent electronically-controlled engine (internal combustion engine) having an accelerator sensor for sensing a pressed amount of an accelerator pedal (i.e., accelerator position). The vehicle controls a throttle position (or intake air quantity) and the like based on the accelerator position sensed with the accelerator sensor, thereby controlling an output of the engine.
For example, Patent document 1 (JP-A-2005-291930) describes a technology that aims to improve safety of such a vehicle. The technology of Patent document 1 compulsorily brings an engine to an idling state when a pressed amount of a brake pedal is equal to or larger than a predetermined value. The predetermined value is a value corresponding to a state where an accelerator pedal and the brake pedal are pressed intentionally at the same time.
When an accelerator pedal and a brake pedal are operated at the same time, a technology described in Patent document 2 (U.S. Pat. No. 6,881,174) suppresses an engine output if it is determined that braking request is stronger than acceleration request based on operation amounts of the accelerator pedal and the brake pedal.
A technology described in Patent document 3 (JP-A-H2-502558) suppresses an engine output if accelerator operation speed is zero when both of an accelerator pedal and a brake pedal are pressed.
Both of the technologies described in Patent documents 1 and 2 secure the safety by suppressing the engine output when both of the accelerator pedal and the brake pedal are pressed. However, for example, in a case where an accelerator pedal of a vehicle such as a towing vehicle is pressed in a state where a brake pedal is strongly pressed to prevent the vehicle from coming down when the vehicle starts on a slope, there is a possibility that the pressed amount of the brake pedal becomes equal to or larger than the predetermined value and the engine output is suppressed according to the technology of Patent document 1. In the same case, according to the technology of Patent document 2, there is a possibility that it is determined that the braking request is stronger than the acceleration request and the engine output is suppressed. Therefore, there is a possibility that the engine output is suppressed and the vehicle cannot be started although a driver intends to accelerate the vehicle.
The technology of Patent document 3 cannot suppress the engine output unless the accelerator operation speed becomes zero even if both of the accelerator pedal and the brake pedal are pressed. Therefore, there is a possibility that the safety at the time when both of the accelerator pedal and the brake pedal are pressed cannot be secured sufficiently.